Toast用法

Toast是Android中用来传递信息的机制。Toast为用户显示一个一定时间内的view，可以是文本、图片等等，但是它并没有取得焦点。

结合RadioButton,RadioGroup,checkbox等控件，我们来看一个小例子。

AndroidControllerTestActivity.java

public class AndroidControllerTestActivity extends Activity {    /** Called when the activity is first created. */private RadioGroup RG = null;private RadioButton malebut = null;private RadioButton femalebut = null;    @Override    public void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.main);        malebut = (RadioButton)findViewById(R.id.maleBut);        femalebut = (RadioButton)findViewById(R.id.femaleBut);        RG = (RadioGroup)findViewById(R.id.sex);        RG.setOnCheckedChangeListener(new RadioGroup.OnCheckedChangeListener()        {            public void onCheckedChanged(RadioGroup group, int checkedId) {            if(malebut.getId() == checkedId){            Toast.makeText(getApplicationContext(),            "you choosed male",Toast.LENGTH_SHORT).show();            }            if(femalebut.getId()==checkedId){            Toast.makeText(getApplicationContext(),            "you choosed female",Toast.LENGTH_SHORT).show();            }            }         }); //匿名内部类    }}

 

运行结果见上图，当你选择对应女性的radiobutton时，界面下方会有一个Toast提示：you choosed femal.

Toast.makeText (Context context, CharSequence text, int duration)

参数：
context：通常为application或activity对象
text： 要显示的文本信息
duration： 显示时间，Toast.LENGTH_SHORT较短，Toast.LENGTH_LONG较长。